Potential of gingival connective tissue to induce keratinization of an alveolar mucosal flap: a long-term histologic and clinical assessment. Case report.

A maxillary canine and premolar showed a 3.0- to 4.0-mm-deep and 3.0- to 4.0-mm-wide recession defect with 2.0- to 3.0-mm zone of attached gingiva. The denuded root surfaces were covered with nonkeratinized alveolar mucosa in a slightly modified bridge flap technique. The coronal displacement of a nonkeratinized alveolar mucosal flap onto a bed of collagenous gingival connective tissue resulted in the development of keratinized epithelium in the previously nonkeratinized mucosa. This was caused by the inductive stimuli of the underlying tissue and observed in the 6-month specimen. The alveolar mucosa displayed its transformed epithelial structural pattern only in segments, achieving full differentiation of its basal complex over a 10-year period, as demonstrated clinically and histologically.